My friends and I used to use it quite a bit back in the 1994 era before the internet was really established. It was kind of like having the internet before anyone else did. I bought a 386 Epson for a grand with a whopping 120 Mb hard drive and thought I was really in heaven. I took that mobile with the KPC3 and it was the equivalent of an aircard at the time. Man, we really thought that was something...texting back and forth mobile from the car!!!
But, it was a neat deal and was handy. It was cool to come home after classes and find the mail light on the KPC3 lit and there were messages from friends just like email we are all used to now.
EDIT: wow I feel old